Complex Calculations: How Drug Use During Pregnancy Becomes a Barrier to Prenatal Care

Pregnant women who use drugs are more likely to receive little or no prenatal care. This study sought to understand how drug use and factors associated with drug use influence women’s prenatal care use. A total of 20 semi-structured interviews and 2 focus groups were conducted with a racially/ethnically diverse sample of low-income women using alcohol and drugs in a California county. Women using drugs attend and avoid prenatal care for reasons not connected to their drug use: concern for the health of their baby, social support, and extrinsic barriers such as health insurance and transportation. Drug use itself is a barrier for a few women. In addition to drug use, women experience multiple simultaneous risk factors. Both the drug use and the multiple simultaneous risk factors make resolving extrinsic barriers more difficult. Women also fear the effects of drug use on their baby’s health and fear being reported to Child Protective Services, each of which influence women’s prenatal care use. Increasing the number of pregnant women who use drugs who receive prenatal care requires systems-level rather than only individual-level changes. These changes require a paradigm shift to viewing drug use in context of the person and society and acceptance of responsibility for unintended consequences of public health bureaucratic procedures and messages about effects of drug use during pregnancy

Complement C3 Deficiency Attenuates Chronic Hypoxia-Induced Pulmonary Hypertension in Mice

Background: Evidence suggests a role of both innate and adaptive immunity in the development of pulmonary arterial hypertension. The complement system is a key sentry of the innate immune system and bridges innate and adaptive immunity. To date there are no studies addressing a role for the complement system in pulmonary arterial hypertension. Methodology/Principal Findings: Immunofluorescent staining revealed significant C3d deposition in lung sections from IPAH patients and C57Bl6/J wild-type mice exposed to three weeks of chronic hypoxia to induce pulmonary hypertension. Right ventricular systolic pressure and right ventricular hypertrophy were increased in hypoxic vs. normoxic wild-type mice, which were attenuated in C3-/- hypoxic mice. Likewise, pulmonary vascular remodeling was attenuated in the C3-/- mice compared to wild-type mice as determined by the number of muscularized peripheral arterioles and morphometric analysis of vessel wall thickness. The loss of C3 attenuated the increase in interleukin-6 and intracellular adhesion molecule-1 expression in response to chronic hypoxia, but not endothelin-1 levels. In wild-type mice, but not C3-/- mice, chronic hypoxia led to platelet activation as assessed by bleeding time, and flow cytometry of platelets to determine cell surface P-selectin expression. In addition, tissue factor expression and fibrin deposition were increased in the lungs of WT mice in response to chronic hypoxia. These pro-thrombotic effects of hypoxia were abrogated in C3-/- mice. Conclusions: Herein, we provide compelling genetic evidence that the complement system plays a pathophysiologic role in the development of PAH in mice, promoting pulmonary vascular remodeling and a pro-thrombotic phenotype. In addition we demonstrate C3d deposition in IPAH patients suggesting that complement activation plays a role in the development of PAH in humans. © 2011 Bauer et al

Antiinflammatory Therapy with Canakinumab for Atherosclerotic Disease

Background: Experimental and clinical data suggest that reducing inflammation without affecting lipid levels may reduce the risk of cardiovascular disease. Yet, the inflammatory hypothesis of atherothrombosis has remained unproved. Methods: We conducted a randomized, double-blind trial of canakinumab, a therapeutic monoclonal antibody targeting interleukin-1β, involving 10,061 patients with previous myocardial infarction and a high-sensitivity C-reactive protein level of 2 mg or more per liter. The trial compared three doses of canakinumab (50 mg, 150 mg, and 300 mg, administered subcutaneously every 3 months) with placebo. The primary efficacy end point was nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death. RESULTS: At 48 months, the median reduction from baseline in the high-sensitivity C-reactive protein level was 26 percentage points greater in the group that received the 50-mg dose of canakinumab, 37 percentage points greater in the 150-mg group, and 41 percentage points greater in the 300-mg group than in the placebo group. Canakinumab did not reduce lipid levels from baseline. At a median follow-up of 3.7 years, the incidence rate for the primary end point was 4.50 events per 100 person-years in the placebo group, 4.11 events per 100 person-years in the 50-mg group, 3.86 events per 100 person-years in the 150-mg group, and 3.90 events per 100 person-years in the 300-mg group. The hazard ratios as compared with placebo were as follows: in the 50-mg group, 0.93 (95% confidence interval [CI], 0.80 to 1.07; P = 0.30); in the 150-mg group, 0.85 (95% CI, 0.74 to 0.98; P = 0.021); and in the 300-mg group, 0.86 (95% CI, 0.75 to 0.99; P = 0.031). The 150-mg dose, but not the other doses, met the prespecified multiplicity-adjusted threshold for statistical significance for the primary end point and the secondary end point that additionally included hospitalization for unstable angina that led to urgent revascularization (hazard ratio vs. placebo, 0.83; 95% CI, 0.73 to 0.95; P = 0.005). Canakinumab was associated with a higher incidence of fatal infection than was placebo. There was no significant difference in all-cause mortality (hazard ratio for all canakinumab doses vs. placebo, 0.94; 95% CI, 0.83 to 1.06; P = 0.31). Conclusions: Antiinflammatory therapy targeting the interleukin-1β innate immunity pathway with canakinumab at a dose of 150 mg every 3 months led to a significantly lower rate of recurrent cardiovascular events than placebo, independent of lipid-level lowering. (Funded by Novartis; CANTOS ClinicalTrials.gov number, NCT01327846.

Microenvironments engineered by inkjet bioprinting spatially direct adult stem cells toward muscle- and bone-like subpopulations

In vivo, growth factors exist both as soluble and as solid-phase molecules, immobilized to cell surfaces and within the extracellular matrix. We used this rationale to develop more biologically relevant approaches to study stem cell behaviors. We engineered stem cell microenvironments using inkjet bioprinting technology to create spatially defined patterns of immobilized growth factors. Using this approach, we engineered cell fate toward the osteogenic lineage in register to printed patterns of bone morphogenetic protein (BMP) 2 contained within a population of primary muscle-derived stem cells (MDSCs) isolated from adult mice. This patterning approach was conducive to patterning the MDSCs into subpopulations of osteogenic or myogenic cells simultaneously on the same chip. When cells were cultured under myogenic conditions on BMP-2 patterns, cells on pattern differentiated toward the osteogenic lineage, whereas cells off pattern differentiated toward the myogenic lineage. Time-lapse microscopy was used to visualize the formation of multinucleated myotubes, and immunocytochemistry was used to demonstrate expression of myosin heavy chain (fast) in cells off BMP-2 pattern. This work provides proof-of-concept for engineering spatially controlled multilineage differentiation of stem cells using patterns of immobilized growth factors. This approach may be useful for understanding cell behaviors to immobilized biological patterns and could have potential applications for regenerative medicine. ©AlphaMed Press

Osteogenic potential of postnatal skeletal muscle-derived stem cells is influenced by donor sex

This study compared the osteogenic differentiation of F-MDSCs and M-MDSCs. Interestingly, M-MDSCs expressed osteogenic markers and underwent mineralization more readily than F-MDSCs; a characteristic likely caused by more osteoprogenitor cells within the M-MDSCs than the F-MDSCs and/or an accelerated osteogenic differentiation of M-MDSCs. Introduction: Although therapies involving stem cells will require both female and male cells, few studies have investigated whether sex-related differences exist in their osteogenic potential. Here, we compared the osteogenic differentiation of female and male mouse skeletal muscle-derived stem cells (F- and M-MDSCs, respectively), a potential cell source for orthopedic tissue engineering. Materials and Methods: F- and M-MDSCs were stimulated with bone morphogenetic protein (BMP)4, followed by quantification of alkaline phosphatase (ALP) activity and expression of osteogenic genes. F- and M-MDSCs were also cultured as pellets in osteogenic medium to evaluate mineralization. Single cell-derived colonies of F- and M-MDSCs were stimulated with BMP4, stained for ALP, and scored as either Low ALP+ or High ALP+ to detect the presence of osteoprogenitor cells. F- and M-MDSCs were transduced with a BMP4 retrovirus (MDSC-BMP4 cells) and used for the pellet culture and single cell-derived colony formation assays. As well, F- and M-MDSC-BMP4 cells were implanted in the intramuscular pocket of sex-matched and sex-mismatched hosts, and bone formation was monitored radiographically. Results and Conclusions: When stimulated with BMP4, both F- and M-MDSCs underwent osteogenic differentiation, although M-MDSCs had a significantly greater ALP activity and a larger increase in the expression of osteogenic genes than F-MDSCs. In the pellet culture assay, M-MDSCs showed greater mineralization than F-MDSCs. BMP4 stimulation of single cell-derived colonies from M-MDSCs showed higher levels of ALP than those from F-MDSCs. Similar results were obtained with the MDSC-BMP4 cells. In vivo, F-MDSC-BMP4 cells displayed variability in bone area and density, whereas M-MDSC-BMP4 cells showed a more consistent and denser ectopic bone formation. More bone formation was also seen in male hosts compared with female hosts, regardless of the sex of the implanted cells. These results suggest that M-MDSCs may contain more osteoprogenitor cells than F-MDSCs, which may have implications in the development of cellular therapies for bone healing. © 2007 American Society for Bone and Mineral Research

Engineering spatial control of multiple differentiation fates within a stem cell population

The capability to engineer microenvironmental cues to direct a stem cell population toward multiple fates, simultaneously, in spatially defined regions is important for understanding the maintenance and repair of multi-tissue units. We have previously developed an inkjet-based bioprinter to create patterns of solid-phase growth factors (GFs) immobilized to an extracellular matrix (ECM) substrate, and applied this approach to drive muscle-derived stem cells toward osteoblasts 'on-pattern' and myocytes 'off-pattern' simultaneously. Here this technology is extended to spatially control osteoblast, tenocyte and myocyte differentiation simultaneously. Utilizing immunofluorescence staining to identify tendon-promoting GFs, fibroblast growth factor-2 (FGF-2) was shown to upregulate the tendon marker Scleraxis (Scx) in C3H10T1/2 mesenchymal fibroblasts, C2C12 myoblasts and primary muscle-derived stem cells, while downregulating the myofibroblast marker α-smooth muscle actin (α-SMA). Quantitative PCR studies indicated that FGF-2 may direct stem cells toward a tendon fate via the Ets family members of transcription factors such as pea3 and erm. Neighboring patterns of FGF-2 and bone morphogenetic protein-2 (BMP-2) printed onto a single fibrin-coated coverslip upregulated Scx and the osteoblast marker ALP, respectively, while non-printed regions showed spontaneous myotube differentiation. This work illustrates spatial control of multi-phenotype differentiation and may have potential in the regeneration of multi-tissue units. © 2011 Elsevier Ltd

Using the emerging Collaborative Cross to probe the immune system.

The Collaborative Cross (CC) is an emerging panel of recombinant inbred (RI) mouse strains. Each strain is genetically distinct but all descended from the same eight inbred founders. In 66 strains from incipient lines of the CC (pre-CC), as well as the 8 CC founders and some of their F1 offspring, we examined subsets of lymphocytes and antigen-presenting cells. We found significant variation among the founders, with even greater diversity in the pre-CC. Genome-wide association using inferred haplotypes detected highly significant loci controlling B-to-T cell ratio, CD8 T-cell numbers, CD11c and CD23 expression. Comparison of overall strain effects in the CC founders with strain effects at QTL in the pre-CC revealed sharp contrasts in the genetic architecture of two traits with significant loci: variation in CD23 can be explained largely by additive genetics at one locus, whereas variation in B-to-T ratio has a more complex etiology. For CD23, we found a strong QTL whose confidence interval contained the CD23 structural gene Fcer2a. Our data on the pre-CC demonstrate the utility of the CC for studying immunophenotypes and the value of integrating founder, CC and F1 data. The extreme immunophenotypes observed could have pleiotropic effects in other CC experiments